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Highly cited papers showcase high-quality research and encompass significant themes in the field. This study examined a total of 435 highly cited papers based on Essential Citation Indicators in the Web of Science (WoS) category of sport sciences with a bibliometric method. In particular, the bibliometric indicators of the highly cited papers including publication venues, authors, countries, institutions, and the top cited publications were presented and analyzed in detail. An Abstract corpus was constructed to help identify the most frequently explored topics. VOSviewer was employed to visualize the co-occurrence networks of keywords. The study revealed the trending information of important contributors at the levels of journals, authors, countries, and institutes. The top cited publications can be grouped into three categories: guidelines, recommendations based on systematic reviews, and evaluations. The most frequently explored topics based on the Abstract corpus and the most frequently used keywords from VOSviewer mapping overlap to a great extent. Specifically, topics such as meta-analysis, systematic review, sport-related concussion, sedentary behavior, football, rehabilitation, and osteoarthritis are among the most frequently mentioned. The results provide the most updated publication characteristics and hot topics of highly cited papers in sport sciences and offer insights for academic researchers in future research. [ABSTRACT FROM AUTHOR]

In this brief communication, we highlight several critical inaccuracies in the paper entitled "A novel methodology for a time-delayed controller to prevent nonlinear system oscillations," identified by the DOI: 10.1177/14613484231195276. The core of the non-perturbative approach discussed in this paper is the introduction of a trial solution with an indeterminate nonlinear frequency. We elucidate the technical missteps and provide necessary corrections. The scrutinized article presents ample opportunities for enhancement, and we propose several amendments. Additionally, we reveal that the numerical outcomes showcased in the mentioned paper expose deficiencies in the proposed approximate solution. With the amendments implemented herein, a more precise numerical solution is achieved. [ABSTRACT FROM AUTHOR]

In this paper, we outline our qualitative protocol for the largest, independent, mixed-method, evaluation of the High Volume-Low Complexity Surgical Hubs programme in England – The MEASURE study. In addition to serving as a protocol paper, we outline the key methodological considerations and adaptations that are needed when designing big qualitative studies – complex (multi-site, multi-stakeholder), multi-method (e.g. interviews, observations, documents) qualitative research involving a large number of participations (n = 100+). This paper expands on our previous methodological work, where we used our experience of undertaking a big qualitative study as part of a mixed-method evaluation of a national emergency care-based initiative, to outline the methodological considerations and uncertainties for designing and analysing "big" qualitative studies. In this paper, we put these considerations into practice by providing a transparent account of our qualitative study design. The methodological reflections which we present are centred around the areas where we feel there is the most uncertainty for big qualitative research: study design, sampling (of case sites and stakeholders) and analysis. Underpinning this uncertainty are broader challenges which utilising this approach incite. Namely, that striving for both breadth (national-level insights) and depth (local variation and context), challenges paradigmatic norms and expectations and forces either methodological innovation, or the adaption of existing qualitative methods. We hope this paper provides transparency and insight into an area of qualitative research which has, potentially due to a perception of "safety in numbers" been inherently trusted and rarely scrutinised. Ultimately, we hope that by providing a transparent account of our study design and the challenges we have faced that we continue to encourage discussion and innovation in this evolving area of qualitative research. [ABSTRACT FROM AUTHOR]

This paper draws together critical learnings from diverse qualitative health research projects in Australia that sought to shift power and focus on the strengths and expertise of people with lived experience who are involved as co-researchers. These projects have included exploring and challenging identities, understanding experiences in treatment programs, critiquing and designing/re-designing services, and sharing experiences with the wider community in novel and innovative ways. Lived experiences included alcohol and other drug dependency, mental health, domestic, family or sexual violence, and living with HIV. This paper provides important learnings and actions about partnering with co-researchers with lived experience. In this paper we draw on a process of reflective discussions that occurred over six months with fortnightly online meetings between co-researchers, including co-authors with lived experience external to academia and university-based researchers, some of whom also have lived-experience that intersects with their research. From this, we distilled key learnings across seven themes: (1) the ethics of ethics, which highlights a need for constant reflection on the ethical issues in co-research; (2) recruiting co-researchers, which focuses on ensuring and integrating a diversity of voices; (3) creating safety for all, which must be a priority of engagement and support self-determination; (4) supporting different ways of partnering, which emphasises the need for diverse roles and ways to contribute on research teams; (5) capacity building and training, which requires ongoing evaluation of needs and tailored responses; (6) positioning, which highlights the need to transition from the idea of vulnerability to a strengths-based perspective of lived experience; and (7) power plays, reflecting the need to disrupt the dynamics and established hierarchies of privileging certain forms of knowledge and expertise. The paper includes recommendations for action against these seven themes. [ABSTRACT FROM AUTHOR]

Regarding debates over researcher insider/outsider positionalities in the field of migration studies, many scholars have proposed various explanations. Some scholars studying migrant populations note that migrant scholars who share identities such as nationality, language, religion, race, ethnicity etc. with their study participants are usually perceived as insiders. Other scholars, however, contend that dynamics of insider/outsider positionalities are situationally shaped during researcher-participant interactions in fieldwork. There is now wide consensus among many scholars that shared social identities between researchers and study participants do not automatically position researchers as insiders. Drawing on secondary literature and my fieldwork encounters, this paper contributes to these debates by proposing typologies for migration researchers to use as analytical tools. The three typologies that map out insider/outsider dynamics during researcher-participant encounters in fieldwork are presuming ethnic insiderness/outsiderness, presuming national insiderness/outsiderness and the indeterminate fieldwork context. This paper argues that researchers' insider/outsider positionalities should not be viewed as pre-determined or fixed formations but as uncertain and situationally constituted. I further argue that migration researchers should not enter the fieldwork with an assumption of automatic insiderness or outsiderness but that they need to view their insider or outsider positionalities as emerging during encounters with research participants. [ABSTRACT FROM AUTHOR]

This scoping review offers insight into researcher well-being when working with sensitive and traumatic topics in a qualitative research context. The study identified existing empirical research concerning researcher well-being and mental health. The databases included SSCI, ASSIA < IBISS, Scopus, Social Policy and Practice, PsycInfo, Social Science Database/Social Science Premium Collection (Proquest), and Open Grey. An international search was conducted, with no time constraints on publication dates to gather as wide a selection as possible. 55 papers met the criteria. We found that the terminology used within the papers was not consistent which necessitated grouping the (self-) reflection/reflexive practices researchers used and categorizing them under the umbrella term SRR practices. The research questions were: 1. Which disciplines or fields are conducting SRR practices on sensitive topics? 2. What SRR practices do researchers employ in the context of sensitive research? 3. What were the self-reported outcomes from using SRR practices as a tool of researchers working on sensitive research? A key finding of the scoping review is that many researchers who work on sensitive topics feel unprepared and receive little or no training or support for SRR practices. This poses particular challenges for early career researchers. We also identified that qualitative researchers have developed a range of SRR practices to manage the emotional impact of their sensitive research work. Many authors of the scoped papers stress the importance of peer-support as well as formal and informal debriefing meetings. Another key SRR practice discussed by many researchers is reflexive journaling. Our scoping review suggests that if it is combined with other activities, self-reflexive journaling can be an excellent way to acknowledge and assess the emotional impact of sensitive research. [ABSTRACT FROM AUTHOR]

The impedance matching is essential in producing high-intensity acoustic waves. This paper studies the impedance calculation methods of modulators and double-chamber Helmholtz resonators based on fluid mechanics, aeroacoustics, and electro-acoustic analogy principles. The results: ① The impedance expression of the resonators is derived. ② The impedance variation law of the chamber volume, the stator size, the air supply pressure, the air supply flow, and the working frequency is calculated. ③ The impedance-matching design scheme of the two-chamber Helmholtz low frequency and high acoustic intensity generator is given. Based on the experimental results of the high acoustic intensity generating device that the author has manufactured in the closed space, the correctness of the impedance calculation and matching design scheme in this paper is verified. This method has guiding significance for the design of high-intensity acoustic generating devices in confined space. [ABSTRACT FROM AUTHOR]

The transverse leaf spring (TLS) suspensions are a promising option for van vehicles due to their high load-carrying capacity and excellent handling stability. However, its ride comfort remains a major challenge. This paper investigates and compares the effects of semi-active and active control strategies to enhance the ride comfort of TLS suspensions. Firstly, a four-degree-of-freedom (4-DOF) half-car model and a multi-body dynamics (MBD) model of the TLS suspensions are established. The MBD model has higher accuracy and can describe the medium and high frequency characteristics of the TLS suspensions, such as the suspension offset frequency and the frequency response function of the body vertical acceleration (BVA). Therefore, based on the MBD half-car model with TLS suspensions, this paper proposes an optimal fuzzy PID active control strategy considering the left and right suspension coupling. The optimization objectives are the BVA, the left and right suspensions dynamic deflection, and the left and right wheels dynamic displacement. The integral absolute error is used as the evaluation criterion. The left and right fuzzy PID controllers' parameters are obtained through particle swarm optimization. Simulation results demonstrate that the particle swarm optimization fuzzy PID active control strategy effectively controls the low-frequency vibration of the TLS suspensions and suppresses the medium- and high-frequency vibration characteristics compared with the traditional skyhook semi-active control strategy. This technology provides a reference for improving the ride comfort of the TLS suspensions. [ABSTRACT FROM AUTHOR]

Inhomogeneous damping distribution leads to the occurrence of complex modes of structures. Complex modes' vibration and acoustic radiation characteristics are different from real modes. This paper studies the complex modal characteristics of inhomogeneously damped plates for forced vibration. We used the state space method to obtain the complex eigenvalues and eigenvectors of the vibration system and calculated the relationship between modal coordinates and frequency under unit force. The results show that the absolute values of the modal coordinates of two conjugate complex eigenvectors are different, and the structure's vibration is dominated by the eigenvectors corresponding to eigenvalues with positive imaginary parts near natural frequencies. When investigating the structural sound radiation in the vibration mode space, each mode's acoustic radiation is not independent but coupled with each other. The influence of the coupling between complex modes on the calculation results of the acoustic radiation power of the plate is studied in this paper. The results show that the coupling effect between modes cannot be ignored when calculating the acoustic radiation power based on complex modes. Finally, the error of calculating acoustic power using the decoupling approximation instead of the complex mode method is analyzed. [ABSTRACT FROM AUTHOR]

Free-play-induced nonlinear dynamic behavior has been one of the most important topics of aeroelastic research in recent decades. In this paper, the describing function (DF) method is developed to investigate the complex dynamic response of a popular all-movable horizontal tail with free-play. Piecewise expressions for the time history and phase portrait of limit cycle oscillation (LCO) are derived by the developed DF method, which is conducive to understand the mechanism of free-play-induced LCO. Another advantage of the developed DF method is the ability to predict the high-order harmonics, which cannot be realized by the classic DF method. A three-dimensional (3D) all-movable horizontal tail model with torsional free-play was designed and manufactured to implement wind tunnel tests via various initial parameters. A good agreement was found between the numerical and experimental results, which can demonstrate the effectiveness of the proposed method. The influence of the initial parameters of the all-movable horizontal tail on the LCO characteristics is analyzed by both numerical calculations and wind tunnel tests. The method and results in this paper can provide a significant reference for the design of all-movable horizontal tail versus the free-play-induced LCO. [ABSTRACT FROM AUTHOR]

Background: The addition of biofeedback and artificial intelligence (AI) in simulation training and serious games has shown promising results in improving the effectiveness of training and can lead to increased engagement, motivation, and retention of information. This systematic literature review explores the integration of biofeedback and artificial intelligence into eXtended reality (XR) training scenarios and is the first review to provide a consolidated overview of applied biofeedback and AI technologies in this area. Method: This review was conducted using keywords related to biofeedback, AI, XR, and training and included papers that: contained the use of biofeedback and AI in XR training scenarios; reported on at least one outcome related to training effectiveness; were published in English; were peer-reviewed; date from 1 January 2016 – 7 February 2022. Results: The results indicate that many studies collect two or more biosignals using a single biosensing device. This is particularly relevant in applied settings, where ease of use and minimal interference in training/education activities is desired. Also, that light, portable devices such as wrist bands, wireless straps, or headbands are preferred. Additionally, eye tracking, electrodermal activity (EDA), and photoplethysmograms (PPG) present as particularly useful biomarkers of stress and/or cognitive load in XR training contexts. A wide variety of machine learning (ML) approaches were used to support biofeedback systems in XR environments. However, a limited number of studies employed real-time analysis of biosignals (just 1% of studies) which indicates current challenges in implementing such systems. Conclusion: The majority of papers meeting the selection criteria were from the fields of education and healthcare. Further research in other domains, such as defense and general industry, is needed to gain a comprehensive understanding of the potential for biofeedback and AI integration in XR training scenarios used in these domains. [ABSTRACT FROM AUTHOR]

Background: Diverticular disease (DD) represents a common gastrointestinal condition that poses a heavy burden on healthcare systems worldwide. A high degree of uncertainty surrounds the therapeutic approaches for the control of symptoms in patients with symptomatic uncomplicated diverticular disease (SUDD) and primary and secondary prevention of diverticulitis and its consequences. Objectives: To review the current knowledge and discuss the unmet needs regarding the management of SUDD and the prevention of acute diverticulitis. Eligibility criteria: Randomized trials, observational studies, and systematic reviews on lifestyle/dietary interventions and medical treatment (rifaximin, mesalazine, and probiotics) of SUDD or prevention of acute diverticulitis. Sources of evidence: The literature search was performed from inception to April 2023, without language restriction, following the modified Preferred Reporting Items for Systematic review and Meta-Analyses (PRISMA) reporting guidelines. References of the papers selected were checked to identify additional papers of potential interest. The final list of references was evaluated by a panel of experts, who were asked to check for any lack of relevant studies. Charting methods: Information on patient population, study design, intervention, control group, duration of the observation, and outcomes assessed was collected by two authors independently. Results: The review shows a high degree of uncertainty about therapeutic interventions, both dietary/lifestyle and pharmacological, in patients with SUDD, because of the scarcity and weakness of existing evidence. Available studies are generally of low quality, heterogeneous, and outdated, precluding the possibility to draw robust conclusions. Similarly, acute diverticulitis prevention has been seldom investigated, and there is a substantial lack of evidence supporting the role of dietary/lifestyle or pharmacological approaches to reduce the risk of diverticulitis. Conclusion: The lack of robust evidence regarding therapeutic options for gastrointestinal symptoms in SUDD patients and for primary and secondary prevention of acute diverticulitis remains an important unmet need in the management of DD. [ABSTRACT FROM AUTHOR]

This essay is a provocation that seeks to contribute to the (re)naissance of African-centered scholarship through a critical interrogation and engagement of words or concepts that exude criticality yet are frequently used superficially. For Africans (globally), conceived by unfavorable imaginations, critical reflection is vital to enable them to engage in deep, reflective analysis of their thoughts, actions, and experiences. Having been dislocated in many ways, (re)examining assumptions, biases, and beliefs and (re)considering alternative perspectives and ideas must preoccupy African researchers. Through an onto-epistemic prism that centers on both Afrocentric assumptions and decolonial thought, the paper interrogates how the prefix "re" extends beyond simplistic meanings like "again" or "repeat" to offer potentialities for African agency. The paper seeks to contribute toward critical African thought and education as well as supporting the pathways for the African Renaissance. The aim is to explore how the prefix "re" can help to empower Africans to shape their own futures. [ABSTRACT FROM AUTHOR]

Cross-language research involving translation is prevalent in the social sciences yet under-discussed in terms of its ethical impact on participants or the translator her/himself. This paper applies a feminist ethics of 'care' to the topic of translation in cross-cultural, cross-language research. We argue for the importance of emotional intelligence and awareness of emotional labor involved in meaningful, ethical translation between the researcher, translator, and participants. The paper itself is a reflexive conversation between a translator and researcher following six months of data collection involving over 120 interviews and 10 work-life histories. We discuss the opportunities and limitations for more emotionally evolved translation in cross-cultural research, discussing specific strategies for caring about, taking care of, caregiving and care receiving through translation. Applying the 'caring through translation' framework promotes deeper collaboration and relationality between researchers, translators, and participants, grounded in feminist ideals of equitable, ethical knowledge production. [ABSTRACT FROM AUTHOR]

Researchers conducting fieldwork, especially in comparative social research, face the complex issue of conceptualizing and practicing positionality. How we position ourselves affects the research approach, the interpretation of the data and, therefore, the whole research process. This paper discusses my own in-between or 'in-out-sider' positionality during my fieldwork studying the experience of youths in social movements in Thailand and Myanmar in 2020 and 2021. Drawing on data from a visit to Thailand and interviews with 40 Myanmar and Thai youths who participated in the movements, this article documents my experience of the subtle nuances of multiple positionalities and how I navigated through the fieldwork as an in-out-sider researcher. In this comparative context, especially, I believe that my in-out-sider positionality facilitated the research process, from interviewing participants to conducting the field visit. The discussion of this contextually situated positionality challenges the typical explanations of the insider/outsider dichotomy, suggesting the need for a rethinking of certain aspects of this explanation, such as the background and experience of the researcher, and the context in which the researcher and the researched interact. This paper therefore contributes to knowledge around this subject and its application, particularly in the context of comparative social research which studies specific groups of youth activists or protestors. [ABSTRACT FROM AUTHOR]

Most nuclear dyads are characterized by some degree of nuclear and conventional asymmetry. This paper argues that these asymmetries create an environment in which deliberate nuclear first use (DNFU) can be rational. This possibility has been discarded in the formal literature on nuclear escalation because of the common reliance on the assumption of mutually assured destruction (MAD). This paper develops a formal model that traces how and under what circumstances two types of DNFU are rational. First, nuclear imbalances and advancements in counterforce technologies create a damage limitation incentive for a strong actor. Second, conventional asymmetry creates an incentive for the coercive use of nuclear weapons by the weaker player. Moreover, this paper illustrates that these asymmetric conditions are a relevant characteristic in important and very different nuclear dyads: DPRK–US, Pakistan–India, and Russia–US. Thus, the model demonstrates the potential core drivers of DNFU in today's nuclear landscape. [ABSTRACT FROM AUTHOR]

This paper studies the distributed convex optimization of bipartite containment control problem for a class of higher order nonlinear multi-agent systems with uncertain states. For the optimization problem, the penalty function is constructed by summing the local objective function of each agent and combining the penalty term formed by the adjacency matrix. For the unknown nonlinear function and unpredictable states in the system, this paper construct radial basis function Neural-networks and state observer for approaching, respectively. In order to avoid "explosion of complexity," under the framework of Lyapunov function theory, we propose the dynamic surface control (DSC) technology and design the distributed adaptive backstepping neural network controller to ensure all the signals remain semi-global uniformly ultimately bounded in the closed-loop system and all agents can converge to the convex hull containing each boundary trajectory as well as its opposite trajectory different in sign. Simulation results confirm the feasibility of the proposed control method. [ABSTRACT FROM AUTHOR]

Traditional qualitative inquiry research methods exhort us to look for the 'good' story tellers who use metaphors to describe their experiences, emotions, and events. This privileges abled-bodied individuals, meaning that without full individual accessibility for people with disability is not achieved. The objective of this paper is to present a case study on inclusion of research participants who live with deafblindness. This case study posits where qualitative story telling spaces currently are; whose voices occupy these narratives; what is said and how it is said: and the performative aspects of the qualitative inquiry currently. Research including people with disability is reflected in the evidence base, however the question that if qualitative methods don't seek to explore and understand these differences, epistemic injustices will be perpetrated. The case study reflects on a research project whose methodology sought to solicit hospital experiences for those living with deafblindness. The Australian study of 18 deafblind participants with wide ranging communication needs, shared in-depth narrative inquiry stories told in: 'snapshots' of moments of disempowerment; through sign and vibrotactile communication; usage of the strong verb with metaphor rarely present except to exclusively describe instances of dehumanisation. Narrative inquiry method when used with people who are deafblind is predominately chaotic with some tense instability for non-signing participants. Emphasis is via repetition, altered pitch and expletives. Touch centricity is fundamental. Dissonance is evident between words used and stories told. The thematic analysis identified a need to reflect epistemically across the creation of any qualitative project from beginning to end, focussing on what is being said and how it is being said or signed or felt. The conclusion of the paper provides a roadmap for future projects to ensure improvements in the enhancing of awareness of different ways of being, doing and telling in qualitative research methods. [ABSTRACT FROM AUTHOR]

Smart building equipment monitoring is a well-established field focused on enhancing contemporary building comfort. The proliferation of Internet connectivity, facilitated by the internet of things (IoT), has transformed buildings from static structures into interactive environments. IoT has witnessed substantial growth across various aspects of daily life, from monitoring environmental conditions to managing building systems and storing data in the cloud. One critical application is the intelligent monitoring and control of building equipment, such as air conditioners, to optimize energy efficiency-a matter of increasing concern for building owners, design experts, and system integrators. Achieving comprehensive energy savings demands a meticulous approach to energy-efficient design and control. This paper's primary objective is to explore and analyze IoT-based energy-saving optimization techniques for intelligent building equipment, integrating building information modeling (BIM) technology. It particularly delves into the energy conservation control algorithm for air-conditioning systems. The research presents a challenge rooted in energy-saving optimization, established upon specific objective functions, followed by a detailed explanation of the energy-saving control algorithm. To validate their approach, the paper outlines a comprehensive experimental design. Over three sessions in August, they conducted control experiments in two distinct areas. Area 1 implemented the energy-saving control methodology discussed in the paper, utilizing virtual parameter enhancement mechanisms, while Area 2 adhered to conventional control methods. The results were enlightening. Area 1 demonstrated superior energy efficiency, consuming 735 kWh compared to Area 2's 819 kWh, signifying an impressive 11.43% reduction in energy consumption thanks to the optimized control strategy. This research underscores the practicality and significance of implementing IoT-based energy-saving strategies, with a focus on smart thermostats, HVAC controllers, and daylight sensors, in intelligent building equipment management to achieve substantial energy conservation gains. [ABSTRACT FROM AUTHOR]

In searching for the optimal control strategy of sub-module capacitance voltage equalization of Modular Multilevel Converter (MMC), the most important issue is how to address the significant increase in computing time of the controller, switching frequency of the sub-module, device switching loss and MMC fault rate led by the increase in the number of sub-modules of the upper/lower bridge arm of the MMC. Therefore, this paper proposes a control strategy based on the retaining factor method + improved quick sort, namely, an improved quick sort algorithm is used to sort the sub-module capacitance voltages to reduce the amount of computation of the MMC controller; at the same time, a retaining factor is introduced to participate in the improved quick sort to significantly reduce the switching frequency of the sub-module. MMC of large ship grid-connected photovoltaic power system is taken as a research object in this paper, a 31-level MMC model is built in Matlab/Simulink. Simulation results verify that the improved quick sort has a good rapidity compared to the algorithms of bubble sort, quick sort, bidirectional bubble sort, and improved merge sort, that the retention factor method has a good frequency reduction effect, and that the proposed retention factor + improved quick sort can provide a good performance compared to improved quick sort and retention factor + improved merge sort under conditions of the normal operation and introducing disturbance. [ABSTRACT FROM AUTHOR]

With the COVID-19 pandemic halting all in-person research in March 2020, many researchers adopted virtual methods to continue their work amid this global crisis. As the pandemic persisted and the safety of participants and researchers remained a priority, virtual research grew in popularity for qualitative researchers. This in turn led to methodological insights on the application and advantages of conducting qualitative research using virtual methods. Virtual methods have been found to enhance participant comfort, facilitate open discussion of sensitive topics, alleviate fatigue in participants and researchers, and result in more engaging and focused interviews. While the body of evidence supporting virtual methods of data collection for nursing and other healthcare disciplines continues to grow, its application in the long-term care (LTC) setting remains underreported. In this paper, we discuss the virtual methods that we developed and implemented to successfully conduct a virtual qualitative single case study in a Canadian LTC home during the COVID-19 pandemic. Considerations from existing literature on virtual methods are discussed in parallel with strategies we implemented to successfully conduct a virtual study in LTC. This paper contributes to the growing body of literature on methodological insights into conducting virtual qualitative research in LTC. We provide evidence-based strategies for the virtual recruitment of study sites, study participants including residents, team members and families, and virtual data collection methods. These recommendations offer insights to overcome challenges and maximize the advantages of virtual methods, to enhance the quality and rigour of virtual qualitative research conducted within LTC settings. [ABSTRACT FROM AUTHOR]

Despite being subject to criticism, qualitative research methodology remains a unique and valuable approach in collecting rich and informative data. However, this may vary from one context to another and researchers understanding of the context. Grounded on the decolonization notion of qualitative research, this paper explains leeways and obstacles in conducting research, reflecting upon the procedural and practical aspects that represent the reality in Tanzania based on two cases. Our paper emphasizes that it is essential to understand and capture the real-world reflective of the voices of the population whom the study targets, which may be easier for local/native researchers. This is because the local/native researchers may be able to explain the research processes and findings in consideration of the socio-cultural settings and political environment. The paper acknowledges that qualitative research requires patience and time, which may have financial implications. It also acknowledges that some populations are facing research fatigue exacerbated by inadequate research dissemination plans. Understanding the context of the study area or topic and applying appropriate methodological approaches to overcome obstacles and gather required adequate and relevant information is thus of importance. [ABSTRACT FROM AUTHOR]

Content analysis, initially a quantitative technique for identifying patterns in qualitative data, has evolved into a widely used qualitative method. However, this evolution has resulted in a confusing array of differing qualitative content analysis approaches that lack clear distinction from other methods. To address these issues, this paper introduces reflexive content analysis, a transtheoretical and flexible researcher-oriented method for the description and reduction of manifest qualitative data. RCA is used to identify patterns in the overt surface meanings of qualitative data through the use of a hierarchical structure of quantifiable analytical strata called codes, subcategories, and categories. Each stratum exists on a continuum of abstraction with codes being the closest to the original data and categories being the most abstract. During each stage of the RCA process, reflexivity is regarded as a valuable analytical resource that is crucial for ensuring adequate description of the data. RCA is intended to be used as method for data analysis, not a methodology, and therefore can be integrated with various methodological and epistemological approaches. This paper provides an introductory guide to conducting RCA. It first presents an overview of existing challenges in qualitative content analysis methods, followed by a rationale for the development of RCA. Then, the foundational principles of RCA and key concepts that support this method are discussed. The paper culminates by outlining the process for conducting an inductive RCA within a qualitative framework, using a previous application of this method as a reference point. [ABSTRACT FROM AUTHOR]

Low-frequency noise has a long wavelength, decays very slowly, and is extremely penetrating. Traditional marine acoustic insulation materials have difficulty achieving effective control of this low-frequency noise. In this paper, a series-parallel arrangement structure of a low-frequency metamaterial is designed, which mainly comprises convoluted channels and Helmholtz cavities in series and a sandwich arrangement of multiple cells (as opposed to the traditional parallel arrangement). We use a numerical method to establish an acoustic-solid coupling model for the metamaterial, consider the influence of thermal and viscous losses on its sound absorption performance, and investigate the sound absorption characteristics and mechanisms of the single-cell and multicell structures. The metamaterial designed in this paper shows an average absorption coefficient of 0.97 in the range of 130–145 Hz. An experimental model was prepared by 3D printing, and the intended sound absorption effect was experimentally verified. [ABSTRACT FROM AUTHOR]

Immigration became an especially thorny and publicly discussed issue with the so-called Refugee Crisis beginning in 2015. The stance of the Czech and Polish governments was dominated by strong anti-Muslim and anti-immigration rhetoric. Still, both countries have witnessed a steady increase in mainly short-term immigration from various Asian countries such as Bangladesh or Pakistan ever since. This paper analyses Czech and Polish migration policies against the backdrop of a historically constructed notion of anti-illegal immigration policy, and category of temporary migration, coupled with the problematic nature of debt-financed migration in Asia. Drawing on ethnographic fieldwork in Czechia and Poland (2018-2021), in-depth and semi-structured interviews with migration experts, academic and grey literature, official documents, and the method of Accidental ethnography, this paper argues that silencing of actual labor immigration in political communication while employing anti-migration rhetoric represents a discursive gap typical for liberal democracies. It further concludes that rendering migrant labor as a temporary commodity and turning a blind eye on recruitment of international migrants represents a continuity practice of migrant labor subordination within the nation-state, originating during colonialism and the advent of capitalism in the nineteenth century. [ABSTRACT FROM AUTHOR]

Three-dimensional elliptical vibration assisted cutting (3D-EVC) technology has been widely used in many high-precision technical fields due to its high-efficiency processing characteristics. However, the hysteresis and nonlinearity caused by the piezoelectric drive in the 3D-EVC system will impact the system control accuracy. This paper mainly studies the hysteresis and nonlinearity of the system, the feedforward-gray predicted fuzzy PID compound controller based on the generalized Bouc-Wen hysteresis nonlinear model and it is designed to realize the hysteresis compensation of the system. In this paper, input voltage and output displacement are represented by a mathematical relationship, and this relationship of the 3D-EVC system will be described by the generalized Bouc-Wen model. The improved flower pollination algorithm (IFPASO) is adopted in the identification process of parameters. A compound control strategy is formed based on traditional feed-forward control combined with fuzzy PID feedback control to compensate for hysteresis and nonlinearity, and an improved gray prediction model is introduced into the feedback loop. The 3D-EVC system tracking experiment verifies the effectiveness of the designed compound controller. Experiments have proved that the hysteresis component of the system is significantly reduced after the use of the compound controller for hysteresis compensation, and the system has a higher degree of stability. [ABSTRACT FROM AUTHOR]

Multi-motor synchronous drive system is increasingly widely used in industry and manufacturing, where its control structure and control strategy affect the quality and efficiency of production. In order to solve the contradiction between fastness and overshoot, and the difficulty in determining the compensation law in the conventional PID, cross-coupling control, and master-slave control strategies used in multi-motor control, this paper proposes a self-coupling PID control strategy based on ring adjacent compensation to reduce the complexity of the control structure. Furthermore, this paper analyzes the self-coupling PID parameter tuning rules and establishes the control structure of the ring coupling strategy, and proves its validity mathematically. The simulation results verify that the proposed strategy provides a fast response speed, high control precision, good disturbance rejection, and synchronization performance. [ABSTRACT FROM AUTHOR]

This paper explores the hegemonic pedagogical-cultures-based narratives that I experienced in my science teaching and learning journey. Furthermore, in this paper, I also envisage different methods for deconstructing the overwhelming influence of hegemony in the science classroom. I focus on two research questions: (1) In what ways could I explore the deep-seated, hegemonic-science, pedagogical culture in my science teaching and learning? (2) How could I envisage the possible ways for deconstructing hegemony in science education? In this autoethnographic inquiry, I used the 'knowledge-constitutive interests' theory as a referent in data text generation and meaning-making. This theoretical lens helped unfold the deep-rooted, hegemony-like singular and absolute scientific knowledge consumption practice. While engaging in reflection-on-/in-/for-actions, I realized the need for curious, contextual and cultural selves and communication as a dance rather than a war for reforming and transforming these deep-seated, hegemonic, pedagogical cultures and identities. Moreover, I also attempt to practise the transdisciplinary STEAM (science, technology, engineering, arts and mathematics) approach for connecting classroom science learning with learners' lives. I believe that it could support reforming/transforming my sit-and-get science teaching. Therefore, I also offer to be involved in a transdisciplinary pedagogy (like STEAM), research and academic writing for transformative curricular praxis and inclusive science learning. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to demonstrate how presuppositional interviews can develop reflexive transparency in grounded theory methodologies. Grounded Theory aims to generate understanding of a given socio-psychological process using a systematic methodology for gathering, analysing and interpreting data. As the researcher is intrinsic to this process, reflexivity is an essential tool to explore and challenge the researcher unknown presuppositions that influence the research process and findings. Reflexivity in practice is challenging as it aims at identifying unknown influences which are by nature, hidden. In this paper, we demonstrate how presuppositional interviews can be applied to Classic and Constructivist grounded theory, and to qualitative research in general. We illustrate this process with two practical case studies, demonstrating how the presuppositional interview can be utilised to enhance transparent reflexive practice. We suggest the presuppositional interview enables higher levels of reflexivity and subsequent positive impact on praxis and the research process. [ABSTRACT FROM AUTHOR]

This article argues that qualitative researchers should focus more attention on producing locally causal explanations for social phenomena. To enable qualitative researchers to achieve this goal, this paper introduces a novel, step-by-step methodology for analysing qualitative data called the 'Realist Phenomenological Method'. The Realist Phenomenological Method does not represent a novel philosophical insight because several studies have already adopted a realistic phenomenological approach in a philosophical context. Rather, this article's novelty lies in its methodological contribution. The introduction of the Realist Phenomenological Method marks an advancement in qualitative research because it is the first formalized analytical methodology to merge methods inspired by critical realism and descriptive phenomenology. Furthermore, this method represents an advancement in qualitative research due to it enabling qualitative researchers to produce causal explanations for social phenomena. This advancement has important implications for qualitative researchers who aim to influence public policy, as any public policymaker who wants to suggest how a social problem can be addressed must first possess an awareness of what is causing the problem. This article begins by introducing the need for a new outlook on causality in qualitative research and outlining how inspiration has been taken from critical realism and descriptive phenomenology in designing the Realist Phenomenological Method. The step-by-step methodology of the Realist Phenomenological Method is then introduced, and an account is provided of how this novel methodology can advance understandings around causal explanations in qualitative research and social science. Interview extracts taken from the author's doctoral dissertation are then used to frame each stage of the Realist Phenomenological Method and demonstrate how the method can be implemented effectively. The paper concludes that the Realist Phenomenological Method can be useful to both qualitative researchers and policymakers who aim to address social issues through effectively identifying the causes of such problems. [ABSTRACT FROM AUTHOR]

In this reflection paper, which stems from my PhD project and explores the gender arrangements and subjective experiences of female breadwinning couples (FBCs) in Pakistan, I delve into the distinctive challenges faced by a male researcher conducting gender research in a patriarchal cultural context. Drawing from both in-person and online fieldwork experiences, which began during the pre-pandemic period and extended through the pandemic into the post-pandemic era, this article unveils the layered intricacies posed by entrenched gender norms, societal expectations and the dynamics of a male researcher probing gendered issue. These challenges were further intensified in online mediums of interviewing, presenting obstacles from participant hesitations surrounding online privacy to inconsistent Internet connectivity and continuous disruptions. This paper also underscores the fluidity and multifaceted nature of the researcher's positionality, navigating interplays of gender, age, and cultural perceptions. My dual role, both an insider (by virtue of my cultural connection to the fieldwork area) and an outsider (owing to my affiliation with a Western academic institution), added layers of complexity to the fieldwork experiences. By juxtaposing in-person and online encounters, a rich tapestry unfolds, depicting both intersecting and unique challenges inherent to each mode of interviewing. Contributions of this reflection paper are multifold, which not only offers valuable insights for future researchers venturing into similar sociocultural contexts but also highlights the nuanced experiences of male-led gender research in predominantly patriarchal settings. The paper also contributes to the discourse on the fluidity of insider-outsider roles, reflexivity, and the methodological resilience and adaptability needed while conducting gender-focused fieldwork within specific cultural contexts. [ABSTRACT FROM AUTHOR]

Blue nevus is a type of uncommon benign pigmented lesion in the skin or the mucosa of human body which is featured by pigmented dendritic melanocytes and spindled melanocytic cells. Sinonasal blue nevus is extremely rare. We reported a sinonasal blue nevus case with the background of pituitary adenoma, type 2 diabetes mellitus, and hypertension (including endoscopic and histological pictures). Further, the existing literature about blue nevus is reviewed. This paper puts a spotlight on the potential correlation between blue nevus with the endocrine system disorder and provides support for further experimental research. [ABSTRACT FROM AUTHOR]

Wartime violence and authoritarian repression against civilians take various forms. Past research has explored the causes and consequences of violence, but no previous work simultaneously assessed the long-term effects of different types of violence on political identities. This paper contends that indiscriminate attacks can reinforce ingroup identity, whereas the role of civilian agency in selective violence may have a detrimental impact. Equipped with original data capturing municipality-level exposure to both selective and indiscriminate violence during the Spanish civil war (1936–1939) in Biscay (Basque Country), this study examines its legacy on voting behavior (1983–2015). Results indicate that fascist airstrikes increased Basque nationalism while selective violence diminished the popularity of Basque parties. Individual and community-level evidence suggests that airstrikes fostered the intergenerational transmission of political attitudes. Violence can boost national identities, but it can also erode them: it depends on the type. [ABSTRACT FROM AUTHOR]

Several studies have found restrictions on minority faith-based communities to be related to the onset of violent religious hostilities. Absent from this work, though, is a consideration of the fact that minority religious discrimination can take different forms, and, consequently, may encourage violence in different ways. This paper seeks to fill this void by examining different forms of minority religious restrictions and their relationship to religious violence. Specifically, we analyze the comparative strength of three basic types of religious discrimination—restrictions on minority religious practices, restrictions on minority religious institutions, and restrictions on conversion and proselytizing —on violence carried out by both religious majority groups and religious minority groups. Interestingly, our analysis shows all three forms of restrictions encourage violence from religious majorities, but not from minorities. We supplement the statistical analysis with a case study of faith-based discrimination and violent religious hostilities in India. [ABSTRACT FROM AUTHOR]

The emerging literature dealing with transnational repression has identified several strategies used by authoritarian states to control and coerce their populations abroad. This article builds on existing research by investigating the domestic determinants of transnational repression. It argues that an increase in domestic repression is likely to lead to a subsequent increase in transnational repression because crackdowns at home drive dissent abroad and incentivize the state to extend its repressive gaze beyond its borders. To evaluate its arguments, the article draws on a database of approximately 1200 cases in which authoritarian states around the world threatened, attacked, extradited, abducted, or assassinated their own citizens abroad between 1991 and 2019. Offering a first quantitative test of domestic drivers of transnational repression, using multivariate regression analysis, the paper finds that as repression intensifies domestically, the likelihood of that state subsequently escalating its transnational repression also increases substantively. [ABSTRACT FROM AUTHOR]

Due to the dominance of ableist narratives, there is a distinct lack of diversity of participants and geographies in education research with students with disabilities. To address this lack, we developed podcasting as a method for DisCrit-informed qualitative research in the form of a pilot project for the first author's doctoral study on the experiences of acquired disability as intersected with policy, race, gender, sexuality, religion, and nationality. Using writing as method of inquiry, in this paper, we reflect on moments of questioning, tensions, challenges, and ethical ponderings that we encountered throughout the creation of the podcast project. These tensions include questions about what digging deep means in DisCrit research, the challenges of negotiating power, ethics, and care, questioning whose stories are worth telling and who gets to tell them and, finally, the epistemological provocations we rubbed against. Specifically, we argue that the creative, digital, and culturally specific properties of podcasting offer a counterstorying approach to ableism, by generating situated knowing about living with a disability. Podcasting, as a DisCrit-informed qualitative approach, may enable researchers' abilities to develop rich, nuanced, and detailed understandings of experiences of disabilities, across geographies, identities, and contexts. [ABSTRACT FROM AUTHOR]

Stimulant laxatives are well established as first- or second-line treatments for constipation and although they have a reliable therapeutic effect, alleged safety concerns still exist, particularly with long-term use. The potential harmful effects on the gastrointestinal system (including carcinogenicity) of the long-term use of diphenylmethane [bisacodyl, sodium picosulfate (SPS)] and senna stimulant laxatives were assessed in a comprehensive review of the publications identified in literature searches performed in PubMed and Embase up to and including June 2023. We identified and reviewed 43 publications of interest. While stimulant laxatives at supratherapeutic doses have been shown to cause structural alterations to surface absorptive cells in animals and humans, these effects are reversible and not considered clinically relevant. No formal long-term studies have demonstrated morphological changes in enteric neural elements or intestinal smooth muscle with bisacodyl or SPS in humans. Furthermore, there is no convincing evidence that stimulant laxatives are associated with the development of colon cancer, and in fact, chronic constipation itself has been reported to potentially increase the risk of colon cancer, therefore, the use of stimulant laxatives might reduce this risk. Many studies suggesting a possible harmful effect from laxatives were limited by their failure to consider confounding factors such as concomitant neurological disease, metabolic disorders, and age. These findings highlight the lack of evidence for the harmful effects of laxatives on the colon, and thus, the benefits of treatment with stimulant laxatives, even in the long-term, should be reconsidered for the management of patients with constipation. Plain language summary: Do stimulant laxatives damage the gut? Stimulant laxatives are widely used treatments for constipation that work by causing the muscles in the gut to contract and so move stool more effectively. Examples of these treatments include senna, bisacodyl and sodium picosulfate. Treatments such as these are typically available without a doctor's prescription and have a long history of helping people relieve their constipation. However, some concerns have been expressed about the safety of these treatments, particularly when they are used for a long time. We did a critical review of published studies of the safety of stimulant laxatives to try to find out whether there is any strong evidence for harm being caused by these treatments. We found 43 papers with information on the gut safety of stimulant laxatives. These studies looked at whether the treatments are associated with changes to gut structure or function and at whether there might be a link between these treatments and bowel cancer. Unfortunately, many of the studies were of poor quality. For instance, they did not look for things, in addition to the laxatives, that could have affected the results, such as the age of the patients, other medications they were taking or whether they had other health conditions that might have affected the bowel. Also, the populations in which the studies were done differed a lot, so they were hard to compare with one another. However, we did not find any strong evidence suggesting that stimulant laxatives damage the gut or cause cancer. We therefore concluded that the harms associated with stimulant laxatives are likely to have been overstated, and that patients should not be denied the benefits of stimulant laxatives for constipation, especially as they have been on the market for a very long time with no serious problems emerging. [ABSTRACT FROM AUTHOR]

Background: Although, several studies have assessed the association of the phospholipase A2 receptor (PLA2R) and HLA-DQA1 SNPs with primary membranous nephropathy (PMN), results were inconsistent and between-studies heterogeneity needs to be investigated. Objectives: The aim of this review was to summarize existing data on the contribution of 10 SNPs in the PLA2R and HLA-DQA1 genes to PMN susceptibility and to investigate the between-studies heterogeneity by subgroup analyses and meta-regressions. Design: This study was performed according to the PRISMA guidelines for systematic reviews and meta-analyses. Data sources and methods: An electronic literature search for eligible studies among all papers published prior to January 10, 2024, was conducted through PubMed, EMBASE, Web of science and Scopus databases. Meta-analyses together with subgroup analyses and meta-regressions were performed for the 10 following SNPs: rs4664308, rs3749117, rs3749119, rs35771982, rs3828323, rs16844715, rs1511223, rs6757188, rs2715918, and rs2187668. Results: Combined analyses revealed a significant increase in PMN risk conferred by the following alleles: rs4664308*A, rs3749117*T, rs3749119*C, rs35771982*G, rs3828323*C, rs16844715*C, rs1511223*A, rs2715918*A, and rs2187668*A, all P -values <.001. Moreover, the PLA2R-rs4664308/HLA-DQA1-rs2187668 interaction was significantly associated with an increased PMN risk, P <.001. However, there was a substantial between-studies heterogeneity for some SNPs. Subgroup analyses by ethnicity for the 9 PLA2R SNPs did not show any cross-ethnic disparity. Inversely, the risk conferred by the HLA-DQA1 rs2187668*A allele was significantly higher in Caucasians (OR [95% CI] = 3.929 [3.251–4.748]) than in Asians (OR [95% CI] = 2.537 [1.94–3.318], P =.007. Besides, meta-regressions revealed for the majority of investigated SNPs significant correlations of the effect size with albumin, 24-hours proteinuria, serum creatinine, and eGFR levels. Hence, the influence on PMN risk conferred by the PLA2R and HLA-DQA1 SNPs was rather noted in patients with a severe disease. Conclusion: This meta-analysis showed that 9 out of the 10 investigated SNPs in PLA2R and HLA-DQA1 genes were associated with increased PMN risk. Heterogeneity could be due to disparate patient groups in terms of disease presentation for almost all SNPs, and ethnicity for the HLA-DQA1 rs2187668 SNP. Registration: This review has been registered on PROSPERO: CRD42024506729. Available from: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42024506729 Plain language summary: Genetic factors in primary membranous nephritis Why was the study done? Primary membranous nephritis (PMN) is the most common etiology of adult-onset nephrotic syndrome. Understanding risk factors, particularly genetic ones, would provide a better understanding of its pathophysiological mechanisms in order to prevent and treat patients more effectively. What did the researchers do? The research team summarized published data on genetic factors associated with PMN including phospholipase A2 receptor (PLA2R) and HLA-DQA1 genes. What did the researchers find? The total number of included studies was 27. Nine out of ten genetic factors were found to be associated with PMN risk. Moreover, we noted significant interaction between PLA2R and HLA-DQA1 in potentializing PMN risk. Nevertheless, there was a significant between-studies heterogeneity which was found to be explained in part by disease severity. What do the findings mean? This study has identified some important some genetic factors associated with PMN together with confounding factors that could influence the aforementioned association. [ABSTRACT FROM AUTHOR]

Background : Health research capacity strengthening (HRCS) has been deemed as a complex, multifaceted, and dynamic activity. Despite this, most studies that assess the effectiveness of health research capacity strengthening programmes have not employed complexity-aware approaches and therefore, evidence on how and why such programmes work across different contexts is underdeveloped. This realist study seeks to elicit the initial programme theories (IPTs) that describe how and why the 'Developing Excellence in Leadership, Training and Science Africa' (DELTAS Africa) programme – one of the flagship research capacity strengthening programmes in Africa – works to generate research capacity outcomes specifically in the participating African universities. Methods and Analysis : A realist review of the DELTAS Africa programme documents, and relevant published papers that report on similar research capacity interventions will be carried out. This will help to both identify the outcome pathways and underlying assumptions of the DELTAS Africa programme, as well as tacit theories as postulated by other researchers. The review evidence will inform the drafting of the initial programme theories (IPTs). Interviews with the DELTAS Africa programme designing team will be conducted using a realist interviewing technique to unearth ontologically deeper insights on context, mechanism, and outcomes. Using the realist context-mechanism-outcome configurational maps, we will identify how contexts (i.e., within the African universities) shape mechanisms (the processes, reasoning, or behaviours triggered by the HRCS activities) through which the programme brings about an outcome at institutional level. Conclusion: The initial programme theories will describe how and why health research capacity strengthening works, for whom and under what circumstances across the participating African universities. The programme theories will provide policy-relevant insights on the generative causal mechanisms of HRCS; evidence that is critically needed to inform the design, implementation, and evaluation of HRCS initiatives. [ABSTRACT FROM AUTHOR]

Tire acoustic cavity resonance (TACR) noise is one kind of low-frequency and narrowband noise that particularly annoys passengers, especially becomes more prominent in electric vehicles. This paper demonstrates a numerical investigation on the TACR noise via the acoustic-structural coupling finite element model. The accuracy of this coupling finite element model is validated both by the analytic method based on the superposition theory of traveling waves and experimental modal tests of tire cavities. According to the simulated models, the influences of external factors including the inflation pressure and road load on the TACR noise are studied. Meanwhile, as the main constituent component in the tire model, the effect of belt cord is also discussed. To design the low-TACR noise tire, various design parameters of the inner contour in tire cavity are analyzed. By the orthogonal test and range analysis, it is found that the contour parameters can slightly affect the modal frequency and sound pressure of TACR noise. Among these, the curvature radius of the tire shoulder ρ 4 , tire sidewall ρ 5 , and half-section height H have a more obvious influence on the TACR noise than the curvature radius of the tire crown region ρ 2 and transition region ρ 3 . Meanwhile, it also illustrates that increasing the curvature radius at the tire shoulder ρ 4 and reducing the half-section height H has a reduction effect on the TACR noise. This study can contribute to the design of low road noise tires. [ABSTRACT FROM AUTHOR]

The extraction of weak acoustic signals under strong background noise is of great significance in the applications of target identification and localization. In this paper, the pulse signal with high randomness is set as the weak signal sound source, random noise and sine sound are used as the background noise. Under the condition of a signal-to-noise ratio of −20 dB, combined with blind source separation and neural network methods, the collected observation signals are subjected to weak sound signal separation and recognition research. The optimization method of centralization and scaling processing is used to eliminate the unfavorable influence of the uncertainty of the separated signal amplitude caused by the blind source separation method on the pattern recognition. The recognition result is verified by the combination of "weak impulse acoustic signal" and "random noise signal," and the output vector (0.99 0.01 0.01) approaches (1 0 0), which is recognized as impulse acoustic signal. By combining blind source separation and neural network methods, the separation and identification of weak pulse signals under the condition of a signal-to-noise ratio of −20 dB can be achieved. [ABSTRACT FROM AUTHOR]

This paper introduces a numerical approach for the fractional-order Rössler chaotic systems and gives error analysis. The effectiveness of the present method is determined by comparing the numerical results of the high-precision difference scheme and predictor-correctors scheme. Some complex dynamical behaviors for the fractional-order Rössler chaotic systems are shown. [ABSTRACT FROM AUTHOR]

This paper investigates the modal parameter identification technique utilizing a drop impact load. A 12-DOF mathematical model of a Railway Vehicle System (RWVS) was constructed, followed by theoretical calculations, simulation analysis, and tests with four different drop impact loads. The responses to these loads were inspected through FFT, and the modal frequencies of the RWVS were determined by the Peak Picking (P-P) method. The simulation demonstrated that four types of drop impact loads can activate the bounce, pitch, and roll modes of the RWVS. The theoretical calculation and simulation analysis revealed that the maximum error of modal frequency identification is no greater than 6.5%. The experimental results verified that the drop impact excitation method can be used to identify the modal parameters of a complex railway vehicle system, which is highly beneficial for the design and verification of the vehicle structure. [ABSTRACT FROM AUTHOR]

Resonance of multi-degree-of-freedom system or structure is a basic and important concept in structural vibration theory, but it lacks a complete and rigorous definition. In order to establish an accurate concept of structural resonance, based on the concept of single-degree-of-freedom system resonance and modal orthogonality, this paper discusses the necessary conditions of system resonance by analyzing the displacement response of multi-degree-of-freedom vibration system, that is, while ensuring that the vibration frequency of the system (a certain natural frequency) is equal to the excitation frequency, its displacement response should also present the corresponding modal shape. An example of simply supported beam is used to illustrate its rationality. At the same time, the theoretical method of pure modal resonance of multi-degree-of-freedom system is given by rational allocation of excitation force. The pure modal resonance of multi-degree-of-freedom system or structure can be realized, which can be used to accurately identify the modal parameters of the structure. It is of great theoretical significance and engineering application value to discriminate the concept of multi-degree-of-freedom system or structure resonance. [ABSTRACT FROM AUTHOR]

The vibration signal of the planetary gear train is easily disturbed by the background noise, so the measured signal is complicated. In order to accurately extract the fault features, the resonance method has been widely used. However, even if the optimal resonance frequency band is found, the in-band noise still exists, so it is necessary to study an effective in-band denoising method. In this paper, an in-band denoising method based on Iterative Singular Value Decomposition (ISVD) is proposed for the fault diagnosis of the secondary sun gear of a planetary gear train, combined with the envelope order spectrum analysis. This method uses the enhanced Wavelet Packet Transform Spectral Kurtosis (WPTSK) to determine the best frequency band for the signal, and uses the ISVD method to realize the signal denoising. It sets a threshold to avoid the destruction of the useful information caused by the excessive iteration, and uses the relationship between the singular values and frequency components to reconstruct the denoised signal. Finally, the signal is converted to the fault characteristic order domain by resampling to identify the fault type of the sun gear from the envelope order spectrum. The simulation and experimental results show that compared with the Empirical Mode Decomposition (EMD) and Variational Mode Decomposition (VMD), the ISVD can effectively suppress the in-band noise and more accurately extract the fault characteristic order of the secondary sun gear under varying speed. [ABSTRACT FROM AUTHOR]

At present, there are few studies considering both nonlinear and fractional characteristics of suspension in vehicle systems. In this paper, a fractional nonlinear model of a quarter vehicle with two-degree-of-freedom (2-DOF) is innovatively proposed to describe the suspension system containing the viscoelastic material metal rubber. Given the lack of a general calculation scheme for the multi-degree-of-freedom fractional-order incremental harmonic balance method (IHBM), a general calculation scheme for the 2-DOF incremental harmonic balance method for nonlinear systems with fractional order is derived. The nonlinear dynamical properties of the presented model are acquired using this method. The accuracy of the proposed method is verified through a comparison with the power series expansion method. Afterward, the effects of the various parameters on the dynamic performance are analyzed. The vibration peak value of the fractional-order model is significantly higher than that of the integer-order model (IOM). Therefore, the suspension parameters should be designed with a margin when using IOM. [ABSTRACT FROM AUTHOR]

This paper presents a novel hybrid algorithm based on CMOGWO-ADNSGA-II to solve the vibration stability problem during the operation of a EMS-type maglev train dynamics model subjected to strong non-linear magnetic buoyancy. The proposed algorithm optimizes the control system parameters of EMS-type maglev train suspensions by combining an improved multi-objective chaotic grey wolf algorithm (CMOGWO) with an improved non-dominated Sorting genetic algorithm-II (ADNSGA-II) to enhance the search capability of the algorithm and ensure population diversity. The efficacy of the algorithm is demonstrated by applying it to the EMS-type maglev train suspension frame control system to find the optimal control parameters. Experimental results show that the system with the optimal parameters applied significantly reduces the suspension gap amplitude and the corresponding standard deviation, as well as the vertical acceleration amplitude and the corresponding standard deviation during operation. The proposed algorithm provides a good solution for EMS-type maglev train suspension vibration control, which can improve its performance and safety. [ABSTRACT FROM AUTHOR]

Noise pollution is the most serious environmental pollution, which seriously affects people's normal life and physical and mental health, as well as normal production work. Therefore, noise control is necessary, but before noise control, the first thing to do is to identify the location of the noise source, and the noise control work is meaningless when the noise cannot be identified. Flat plate structures are a fundamental part of complex ship structures, and their vibration, noise, and their interrelationships when excited by the outside world are receiving increasing attention. The core of the research in this paper is the identification of the sound source of the vibrating plate. A method combining phase conjugation with interior boundary element method is developed for the identification of the pressure and normal velocity distribution of a vibrating plate. An interior problem is formed by enclosing the phase conjugation array plane and the plate surface. The pressures at the array elements are phase-conjugated as the specified pressure boundary condition. The impedance relationship between the surface pressure and the surface normal velocity of the plate is utilized as a specified impedance boundary condition. The interior boundary element method is applied to solve the interior problem. The identification of the surface pressure and normal velocity distribution is studied numerically. The numerical results show that with the array located in the near field the proposed method achieves subwavelength focusing to identify the surface pressure and normal velocity distribution and clearly shows the response shapes. [ABSTRACT FROM AUTHOR]

This paper focuses upon the famous sculpture of the Dying Gaul, situated in the Capitoline Museum in Rome, in order to read and to rethink discourses of resilience in the Anthropocene. The Anthropocene poses fundamental questions to understandings of 'bouncing back' or imaginaries of 'sustainable futures'. There can be no affirmative futural imaginaries if saving the world requires the destruction and sacrifice of innumerable others. Thinking with Byron's reflections upon the Dying Gaul enables us to approach resilience from a radically different perspective, one that (read in conjunction with the work of Claire Colebrook, Karen Barad, Christina Sharpe, Dionne Brand and Saidiya Hartman amongst other contemporary theorists) we call a 'posthumous' approach. 'Posthumous resilience' refuses the lure of affirmation, of imaginaries of salvage and salvation, and instead seeks to generate an ethic of 'active withdrawal' that points beyond the temporal and spatial constraints of the colonial, imperial, imagination. We conclude with a reflection on how posthumous discourses of 'active withdrawal' can be the basis of generative politics of refusal which hold open conceptions of justice and seek to break from cycles of violence. [ABSTRACT FROM AUTHOR]

This study investigates political decisions and epidemiological developments. Employing a quantitative approach, this paper examines proportions of votes advocating Brexit with the proportional rates of Covid-19 vaccinations among individuals aged 18 years and above. A discernible pattern suggests a link between lower vaccination rates and pro-Brexit inclinations, validating the theory of disinformation affecting decision-making. This research finds a correlative relationship between political behaviour in voting for Brexit, and epidemiological outcomes measured by the uptake of vaccinations among various urban centres, towns, and local governmental jurisdictions within the United Kingdom. However, the results also show socioeconomic control variables are statistically more significant in predicting vaccination rates. [ABSTRACT FROM AUTHOR]